package sqlengine.queryOptimization;

public class ColumnInfo {
	String tableName;
	String columnName;
	int columnValueNum;
	int id;
	ColumnInfo reference;
	public int getColumnValueNum(){
		if(columnValueNum == 0){ // have not been counted
			// count
			//columnValueNum = 
			return columnValueNum;
		} else if(columnValueNum == -1){ // refer to another column
			return reference.getColumnValueNum();
		} else 
			return columnValueNum;
	}
}
